Figure 2. . . No evidence of productive Norwalk virus (NV) replication in 3-dimensional intestinal aggregates by quantitative reverse transcription PCR analysis. Supernatants (sups) and cell pellets were harvested for RNA at 0, 6, 24, 48, 72, and 96 hours postinoculation (hpi) with live and inactivated NV and analyzed by quantitative reverse transcription PCR. There was no significant increase (p>0.05) in NV RNA copy number over time in the supernatants or cell pellets relative to input virus. Error bars indicate SEM.